Spinal implant system and method for lumbar and lumbosacral fusion

ABSTRACT

A spinal implant comprises an implant body extending between an anterior surface and a posterior surface, and including a first vertebral engaging surface and a second vertebral engaging surface. The implant body includes an inner surface that defines at least a first cavity and a second cavity. The cavities are oriented to implant fasteners in alignment with an oblique surgical pathway relative to a bilateral axis of a subject body and adjacent an anterior portion of an intervertebral space of the subject body. Systems and methods are disclosed.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefits of U.S. Provisional PatentApplication No. 61/887,803 filed Oct. 7, 2013, the contents of whichbeing hereby incorporated in its entirety by reference.

TECHNICAL FIELD

The present disclosure generally relates to medical devices for thetreatment of musculoskeletal disorders, and more particularly to aspinal implant system and a method for treating a spine, which employ anoblique pathway suitable for accessing disc spaces in the lower lumbarregion, for example, an L5-S1 disc space.

BACKGROUND

Spinal pathologies and disorders such as scoliosis and other curvatureabnormalities, kyphosis, degenerative disc disease, disc hemiation,osteoporosis, spondylolisthesis, stenosis, tumor, and fracture mayresult from factors including trauma, disease and degenerativeconditions caused by injury and aging. Spinal disorders typically resultin symptoms including deformity, pain, nerve damage, and partial orcomplete loss of mobility.

Non-surgical treatments, such as medication, rehabilitation and exercisecan be effective, however, may fail to relieve the symptoms associatedwith these disorders. Surgical treatment of these spinal disordersincludes fusion, fixation, correction, discectomy, laminectomy andimplantable prosthetics. As part of these surgical treatments, spinalconstructs, such as, for example, bone fasteners, spinal rods andinterbody devices can be used to provide stability to a treated region.For example, during surgical treatment, surgical instruments can be usedto deliver components of the spinal constructs to the surgical site forfixation with bone to immobilize a joint. This disclosure describes animprovement over these prior art technologies.

SUMMARY

Systems and methods of use for accessing lower lumbar disc spaces via anoblique lateral approach are provided. In some embodiments, a spinalimplant comprises an implant body extending between an anterior surfaceand a posterior surface, and including a first vertebral engagingsurface and a second vertebral engaging surface. The implant bodyincludes an inner surface that defines at least a first cavity and asecond cavity. The cavities are oriented to implant fasteners inalignment with an oblique surgical pathway relative to a bilateral axisof a subject body and adjacent an anterior portion of an intervertebralspace of the subject body.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will become more readily apparent from thespecific description accompanied by the following drawings, in which:

FIG. 1 is a plan view of one embodiment of a system in accordance withthe principles of the present disclosure disposed with a subject body;

FIG. 2 is a plan view of one embodiment of a system in accordance withthe principles of the present disclosure disposed with a subject body;

FIG. 3 is a plan view of components of one embodiment of a system inaccordance with the principles of the present disclosure disposed with asubject body;

FIG. 4 is a plan view of components of one embodiment of a system inaccordance with the principles of the present disclosure disposed with asubject body;

FIG. 4A is a perspective view of components of one embodiment of asystem in accordance with the principles of the present disclosure;

FIG. 4B is a perspective view of the components shown in FIG. 4A withparts separated;

FIG. 5 is a perspective view of a component of one embodiment of asystem in accordance with the principles of the present disclosure;

FIG. 6 is a plan view of components of one embodiment of a system inaccordance with the principles of the present disclosure;

FIG. 6A is a plan view of components of one embodiment of a system inaccordance with the principles of the present disclosure;

FIG. 7 is a perspective view of a component of one embodiment of asystem in accordance with the principles of the present disclosure;

FIG. 8 is a perspective view of components of one embodiment of a systemin accordance with the principles of the present disclosure;

FIG. 9 is a perspective view of components of one embodiment of a systemin accordance with the principles of the present disclosure;

FIG. 10 is a top view of components of one embodiment of a system inaccordance with the principles of the present disclosure;

FIG. 11 is a top view of components of one embodiment of a system inaccordance with the principles of the present disclosure;

FIG. 12 is a perspective view of components of one embodiment of asystem in accordance with the principles of the present disclosuredisposed with a subject body;

FIG. 12A is a perspective view of the components and subject body shownin FIG. 12;

FIG. 13 is an axial view of the components and subject body shown inFIG. 12;

FIG. 14 is an axial view of components of one embodiment of a system inaccordance with the principles of the present disclosure disposed withvertebrae;

FIG. 15 is an axial view of components of the system and the vertebraeshown in FIG. 14;

FIG. 16 is a perspective view of components of one embodiment of asystem in accordance with the principles of the present disclosure;

FIG. 17 is a plan view of components of one embodiment of a system inaccordance with the principles of the present disclosure disposed withvertebrae;

FIG. 18 is a plan view of components of one embodiment of a system inaccordance with the principles of the present disclosure disposed withvertebrae;

FIG. 18A is a side view of components and the vertebrae shown in FIG.18;

FIG. 18B is a side view of components and the vertebrae shown in FIG.18;

FIG. 19 is a perspective view of components of one embodiment of asystem in accordance with the principles of the present disclosure;

FIG. 20 is a perspective view of the components shown in FIG. 19;

FIG. 21 is a side view of components of one embodiment of a system inaccordance with the principles of the present disclosure;

FIG. 22 is a detail side view of the components shown in FIG. 21;

FIG. 23 is a detail top view of the components shown in FIG. 21;

FIG. 24 is a detail top view of the components shown in FIG. 21 disposedwith vertebrae;

FIG. 25 is a side view of components of one embodiment of a system inaccordance with the principles of the present disclosure disposed withvertebrae;

FIG. 26 is a side view of components of one embodiment of a system inaccordance with the principles of the present disclosure;

FIG. 27 is a side view of components of one embodiment of a system inaccordance with the principles of the present disclosure;

FIG. 27A is a perspective view of components of one embodiment of asystem in accordance with the principles of the present disclosure;

FIG. 28 is a plan view of components and vertebrae shown in FIG. 24;

FIG. 29A is a perspective view of the L5-S1 level;

FIG. 29B is a plan view of the L5-S1 level;

FIG. 30A is a perspective view of components of one embodiment of aninserter and cage in preparation for insertion according to oneembodiment;

FIG. 30B is a plan view of components of one embodiment of an inserterand cage in preparation for insertion according to one embodiment;

FIG. 31A is a perspective view of components of one embodiment of aninserter and cage in the final steps of insertion according to oneembodiment; and

FIG. 31B is a plan view of components of one embodiment of an inserterand cage in the final steps of insertion according to one embodiment.

DETAILED DESCRIPTION

The exemplary embodiments of the surgical system and related methods ofuse disclosed are discussed in terms of medical devices for thetreatment of musculoskeletal disorders and more particularly, in termsof a surgical system for implant delivery to a surgical site and amethod for treating a spine, which employ an oblique surgical pathway.In one embodiment, the systems and methods of the present disclosure areemployed with a spinal joint fusion, for example, with a cervical,thoracic, lumbar and/or sacral region of a spine. In one embodiment, anexemplary set of implants and instruments is disclosed for performing aspinal joint fusion in the L5-S1 disc space from an oblique-lateralsurgical pathway at a selected oblique angle from the medial plane ofthe patient. For example, in some exemplary embodiments, the surgicalpathway is established at approximately 15 degrees from a medial planeof a patient while the patient is positioned on their side, see FIGS. 1and 2, generally.

In one embodiment, the surgical system is employed with a methodincluding an oblique lateral interbody fusion (OLIF) procedure in thelower lumbar region between an L5 vertebral body and a sacrum S1approach using location of a retroperitoneal anatomy and relatedvascular structures, which may include trans abdominal andretroperitoneal. In one embodiment, the OLIF procedure includes asurgical pathway that is laterally positioned relative to an anteriorlumbar interbody fusion (ALIF) retroperitoneal approach. In oneembodiment, the procedure avoids dissection of the retroperitoneal spaceand can be done with a small incision using semi-constrained retractors.In one embodiment, the OLIF procedure avoids the psoas muscle, the iliaccrest and both branches of the vasculature in the lower lumbar region.Various embodiments may allow for an oblique lower lumbar procedure thatis approached between branched vasculature on an anterior side of apatient in a lower lumbar region, for example, at the L5-S1 vertebrallevels.

In one embodiment, the surgical system includes a surgical pathway thatis 0-30 degrees off a direct anterior axis. In one embodiment, thesurgical pathway is 15 degrees off a direct anterior axis. In oneembodiment, the surgical system comprises surgical instruments thatinclude image guided technologies, such as, for example, surgicalnavigation components employing emitters and sensors, which may beemployed to track introduction and/or delivery of the components of thesurgical system including the surgical instruments to a surgical site.

In one embodiment, the surgical system includes an interbody implanthaving threaded locking mechanisms and/or cavities defined therein toorient fasteners oblique relative to a bilateral axis of a subject body.In one embodiment, the surgical system includes an interbody implanthaving flanges that extend along the OLIF pathway for integratedfixation. In one embodiment, the surgical system includes an interbodyimplant with a plate. The interbody implant and plate can be insertedtogether or separately. In one embodiment, the surgical system includesan interbody implant having no or zero profile integrated screws. In oneembodiment, the surgical system includes an interbody implant having aposterior cutaway configured to avoid foramen. In one embodiment, theinterbody implant can include various shapes, such as, for example,wide, crescent or articulating. In one embodiment, the interbody implantincludes a bullet nose.

In one embodiment, the surgical system includes surgical instruments,such as, for example, flexible or semi-constrained retractors utilizedto facilitate insertion of one or more components of the surgicalsystem. In one embodiment, a handheld retractor is utilized tofacilitate spacing of retractor blades. In one embodiment, the surgicalinstruments include an all-in-one inserter such that instruments, suchas, for example, a drill, tap or awl are guided by the inserter and theinserter is configured to guide screws into tissue.

In one embodiment, the surgical system includes a retractor orientedwith a handle on the patient's cephalad side. In one embodiment, thesurgical system includes a retractor having three blades. In oneembodiment, the blades of the retractor are positioned adjacent tovessels to protect the vessels.

The present disclosure may be understood more readily by reference tothe following detailed description of the embodiments taken inconnection with the accompanying drawing figures, which form a part ofthis disclosure. It is to be understood that this application is notlimited to the specific devices, methods, conditions or parametersdescribed and/or shown herein, and that the terminology used herein isfor the purpose of describing particular embodiments by way of exampleonly and is not intended to be limiting. Also, as used in thespecification and including the appended claims, the singular forms “a,”“an,” and “the” include the plural, and reference to a particularnumerical value includes at least that particular value, unless thecontext clearly dictates otherwise. Ranges may be expressed herein asfrom “about” or “approximately” one particular value and/or to “about”or “approximately” another particular value. When such a range isexpressed, another embodiment includes from the one particular valueand/or to the other particular value. Similarly, when values areexpressed as approximations, by use of the antecedent “about,” it willbe understood that the particular value forms another embodiment. It isalso understood that all spatial references, such as, for example,horizontal, vertical, top, upper, lower, bottom, left and right, are forillustrative purposes only and can be varied within the scope of thedisclosure. For example, the references “upper” and “lower” are relativeand used only in the context to the other, and are not necessarily“superior” and “inferior”.

Further, as used in the specification and including the appended claims,“treating” or “treatment” of a disease or condition refers to performinga procedure that may include administering one or more drugs to apatient (human, normal or otherwise or other mammal), employingimplantable devices, and/or employing instruments that treat thedisease, such as, for example, micro discectomy instruments used toremove portions bulging or herniated discs and/or bone spurs, in aneffort to alleviate signs or symptoms of the disease or condition.Alleviation can occur prior to signs or symptoms of the disease orcondition appearing, as well as after their appearance. Thus, treatingor treatment includes preventing or prevention of disease or undesirablecondition (e.g., preventing the disease from occurring in a patient, whomay be predisposed to the disease but has not yet been diagnosed ashaving it). In addition, treating or treatment does not require completealleviation of signs or symptoms, does not require a cure, andspecifically includes procedures that have only a marginal effect on thepatient. Treatment can include inhibiting the disease, e.g., arrestingits development, or relieving the disease, e.g., causing regression ofthe disease. For example, treatment can include reducing acute orchronic inflammation; alleviating pain and mitigating and inducingre-growth of new ligament, bone and other tissues; as an adjunct insurgery; and/or any repair procedure. Also, as used in the specificationand including the appended claims, the term “tissue” includes softtissue, muscle, ligaments, tendons, cartilage and/or bone unlessspecifically referred to otherwise.

The following discussion includes a description of a surgical system andrelated methods of employing the surgical system in accordance with theprinciples of the present disclosure. Alternate embodiments are alsodisclosed. Reference will now be made in detail to the exemplaryembodiments of the present disclosure, which are illustrated in theaccompanying figures. Turning to FIGS. 1-28, there are illustratedcomponents of a surgical system, such as, for example, a spinal implantsystem 10.

The components of spinal implant system 10 can be fabricated frombiologically acceptable materials suitable for medical applications,including metals, synthetic polymers, ceramics and bone material and/ortheir composites, depending on the particular application and/orpreference of a medical practitioner. For example, the components ofspinal implant system 10, individually or collectively, can befabricated from materials such as stainless steel alloys, commerciallypure titanium, titanium alloys, Grade 5 titanium, super-elastic titaniumalloys, cobalt-chrome alloys, stainless steel alloys, superelasticmetallic alloys (e.g., Nitinol, super elasto-plastic metals, such as GUMMETAL® manufactured by Toyota Material Incorporated of Japan), ceramicsand composites thereof such as calcium phosphate (e.g., SKELITE™manufactured by Biologix Inc.), thermoplastics such aspolyaryletherketone (PAEK) including polyetheretherketone (PEEK),polyetherketoneketone (PEKK) and polyetherketone (PEK), carbon-PEEKcomposites, PEEK-BaSO₄ polymeric rubbers, polyethylene terephthalate(PET), fabric, silicone, polyurethane, silicone-polyurethane copolymers,polymeric rubbers, polyolefin rubbers, hydrogels, semi-rigid and rigidmaterials, elastomers, rubbers, thermoplastic elastomers, thermosetelastomers, elastomeric composites, rigid polymers includingpolyphenylene, polyamide, polyimide, polyetherimide, polyethylene,epoxy, bone material including autograft, allograft, xenograft ortransgenic cortical and/or corticocancellous bone, and tissue growth ordifferentiation factors, partially resorbable materials, such as, forexample, composites of metals and calcium-based ceramics, composites ofPEEK and calcium based ceramics, composites of PEEK with resorbablepolymers, totally resorbable materials, such as, for example, calciumbased ceramics such as calcium phosphate such as hydroxyapatite (HA),corraline HA, biphasic calcium phosphate, tricalcium phosphate, orfluorapatite, tri-calcium phosphate (TCP), HA-TCP, calcium sulfate, orother resorbable polymers such as polyaetide, polyglycolide,polytyrosine carbonate, polycaroplaetohe and their combinations,biocompatible ceramics, mineralized collagen, bioactive glasses, porousmetals, bone particles, bone fibers, morselized bone chips, bonemorphogenetic proteins (BMP), such as BMP-2, BMP-4, BMP-7, rhBMP-2, orrhBMP-7, demineralized bone matrix (DBM), transforming growth factors(TGF, e.g., TGF-β), osteoblast cells, growth and differentiation factor(GDF), insulin-like growth factor 1, platelet-derived growth factor,fibroblast growth factor, or any combination thereof.

Various components of spinal implant system 10 may have materialcomposites, including the above materials, to achieve various desiredcharacteristics such as strength, rigidity, elasticity, compliance,biomechanical performance, durability and radiolucency or imagingpreference. The components of spinal implant system 10, individually orcollectively, may also be fabricated from a heterogeneous material suchas a combination of two or more of the above-described materials. Thecomponents of spinal implant system 10 may be monolithically formed,integrally connected or include fastening elements and/or instruments,as described herein. In one embodiment, an interbody cage 12, describedherein, may be formed substantially of biocompatible polymer, such asPEEK, and selectively coated with a biocompatible metal, such astitanium, or a bone-growth promoting material, such as HA. In some suchembodiments, titanium may be plasma sprayed onto surfaces of interbodycage 12 so as to modify the radiographic signature of cage 12 and/orimprove the prospects of bony ongrowth to cage 12 by virtue of theapplication of a porous or semi-porous coating of titanium.

Spinal implant system 10 may be employed, for example, with minimallyinvasive procedures, including percutaneous techniques, mini-opensurgical techniques and/or open surgical techniques to deliver andintroduce instrumentation and/or implants, such as, for example, aninterbody implant, at a surgical site within a subject body B of apatient, which includes, for example, a spine having vertebrae V, asshown in FIGS. 1 and 2. In some embodiments, the implant can includespinal constructs, such as, for example, bone fasteners, spinal rods,connectors and/or plates. In other embodiments, various components ofthe spinal implant system 10 may also be utilized in “open” ortraditional spinal surgical techniques. In many of the embodimentsdescribed herein, the patient is positioned on their side for thesurgical procedure and the surgeon may stand on an anterior side of thepatient so as to be capable of standing directly above theoblique-anterior and/or oblique lateral surgical pathway established.

Spinal implant system 10 includes an implant body, such as, for example,interbody cage 12, as shown in FIGS. 14 and 15. Cage 12 extends betweenan anterior surface 14 and a posterior surface 16. Anterior surface 14is configured to face an anterior side of body B and be disposedadjacent an anterior portion of vertebrae, such as, for example, ananterior portion A1 of an L5-S1 intervertebral space of vertebrae V.Posterior surface 16 is configured to face a posterior side of body Band be disposed adjacent a posterior portion of vertebrae, such as, forexample, a posterior portion of the L5-S1 intervertebral space.

Cage 12 includes a first vertebral engaging surface 18 and a secondvertebral engaging surface 20. Surface 18 is substantially planar andconfigured to engage endplate tissue of a vertebral body, such as, forexample, an endplate E1 of an L5 vertebral body, as shown in FIG. 2.Surface 20 is configured to engage endplate tissue of a vertebral body,such as, for example, an endplate E2 of a sacrum S1. In someembodiments, surfaces 18, 20 may be rough, textured, porous,semi-porous, dimpled, knurled, toothed, grooved and/or polished suchthat it facilitates engagement with tissue. In some embodiments, thevertebral tissue may include intervertebral tissue, endplate surfacesand/or cortical bone.

Cage 12 may be provided with a substantially cylindrical cross sectionconfiguration and includes an inner surface 22 that defines an opening23 configured to receive an agent, which may include bone graft (notshown) and/or other materials, as described herein, for employment in afixation or fusion treatment. In some embodiments, the cross-sectionalgeometry of cage 12 may have various configurations, such as, forexample, round, oval, oblong, triangular, polygonal having planar orarcuate side portions, irregular, uniform, non-uniform, consistent,variable, horseshoe shape, U-shape or kidney bean shape. In someembodiments, cage 12 includes an outer surface 25 that is smooth oreven. In some embodiments, outer surface 25 may be rough, textured,porous, semi-porous, dimpled and/or polished.

Inner surface 22 includes internally threaded portions and/ornon-threaded portions that define cavities, such as, for example, ascrew hole 24 and a screw hole 26, as shown in FIG. 14. Screw hole 24extends along the body of cage 12 in a transverse configuration relativeto the surfaces of cage 12, described herein, for fixation with tissue.Screw hole 24 is oriented with the body of cage 12 in substantialalignment with an oblique surgical pathway P formed in body B, asdescribed herein. Surgical pathway P is oriented oblique relative to abilateral axis XB of body B. In some embodiments, surgical pathway P isdisposed at an oblique angle α relative to axis XB. In some embodiments,angle α is in a range of approximately 0-60 degrees. In someembodiments, substantial alignment of all or only a portion of screwhole 24 with all or only a portion of surgical pathway P includesco-axial, spaced apart, offset, angularly offset and/or parallelalignment.

Screw hole 24 defines an axis X1 oriented oblique relative to axis XBsuch that screw hole 24 implants a fastener, as described herein,oblique relative to axis XB and adjacent portion A1. Axis XB lies in atransverse plane TP defined by body B corresponding to the L5-S1intervertebral space, as shown in FIG. 1. Axis XB also lies in asagittal plane SP, as shown in FIG. 2, defined by body B such thatplanes TP, SP intersect adjacent axis XB. Vertebrae V defines asubstantially longitudinal axis L, which lies in plane SP.

Axis X1 is disposed in substantial alignment with surgical pathway P andat an oblique angle α1 relative to axis XB. In some embodiments, angleα1 is in a range of approximately 0-60 degrees. In one embodiment, angleα1 is approximately 15 degrees relative to axis XB and substantiallyaligned with surgical pathway P such that screw hole 24 is configured toreceive a fastener via surgical pathway P. In some embodiments, screwhole 24 is also disposed at an angular orientation relative to plane TPand/or axis XB such that a fastener is delivered to a surgical siteincluding the L5-S1 intervertebral space via surgical pathway P andoriented to penetrate endplate tissue of a vertebral body, such as, forexample, an endplate E2 of a sacrum S1. In some embodiments, screw hole24 and/or the body of cage 12 may be disposed at an angular orientationrelative to plane TP and/or axis XB such that a fastener is oriented topenetrate endplate tissue of a vertebral body.

Outer surface 25 includes an oblique surface 44 that defines an opening46 disposed in communication and substantial alignment with screw hole24. Oblique surface 44 is oriented with cage 12 and in substantialalignment with surgical pathway P. Opening 46 is configured to guide afastener into screw hole 24 relative to axis XB and in substantialalignment with surgical pathway P. In some embodiments, oblique surface44 is configured for mating engagement with a surgical instrument, suchas, for example, an inserter T1, as shown in FIG. 14, which deliverscage 12 adjacent a surgical site via surgical pathway P, as describedherein. In some embodiments, system 10 may comprise various surgicalinstruments, such as, for example, drivers, extenders, reducers,spreaders, distractors, blades, clamps, forceps, elevators and drills,which may be alternately sized and dimensioned, and arranged as a kit.In some embodiments, system 10 may comprise various surgicalinstruments, such as, for example, drivers, extenders, reducers,spreaders, distractors, blades, clamps, forceps, elevators and drills,which may be alternately sized and dimensioned, and arranged as a kit.In some embodiments, system 10 may comprise the use of microsurgical andimage guided technologies, such as, for example, surgical navigationcomponents employing emitters and sensors, which may be employed totrack introduction and/or delivery of the components of system 10including the surgical instruments to a surgical site. See, for example,the surgical navigation components and their use as described in U.S.Pat. Nos. 6,021,343, 6,725,080, 6,796,988, the entire contents of eachof these references being incorporated by reference herein. An exemplaryall-in-one inserter and guide instrument for cage 12 is shown, forexample, in FIGS. 19 and 20 described herein.

Screw hole 26 extends along the body of cage 12 in a transverseconfiguration relative to the surfaces of cage 12, described herein, forfixation with tissue. Screw hole 26 is oriented with the body of cage 12in substantial alignment with surgical pathway P. In some embodiments,substantial alignment of all or only a portion of screw hole 26 with allor only a portion of surgical pathway P includes co-axial, spaced apart,offset, angularly offset and/or parallel alignment.

Screw hole 26 defines an axis X2 oriented oblique relative to axis XBsuch that screw hole 26 implants a fastener, as described herein,oblique relative to axis XB and adjacent portion A1. Axis X2 is disposedin substantial alignment with surgical pathway P and at an oblique angleα2 relative to axis XB. In some embodiments, angle α2 is in a range ofapproximately 0-60 degrees. In one embodiment, angle α2 is approximately15 degrees relative to axis XB and substantially aligned with surgicalpathway P such that screw hole 26 is configured to receive a fastenervia surgical pathway P. In some embodiments, screw hole 26 is alsodisposed at an angular orientation relative to plane TP and/or axis XBsuch that a fastener is delivered to a surgical site including the L5-S1intervertebral space via surgical pathway P and oriented to penetrateendplate tissue of a vertebral body, such as, for example, an L5vertebral body. In some embodiments, screw hole 26 and/or the body ofcage 12 may be disposed at an angular orientation relative to plane TPand/or axis XB such that a fastener is oriented to penetrate endplatetissue of a vertebral body. In some embodiments, angle α, α1 and/or α2may be equal, substantially equivalent and/or different. In someembodiments, surgical pathway P, axis X1 and/or axis X2 may be co-axial,spaced apart, offset, angularly offset and/or parallel alignment.

Oblique surface 44 defines an opening 48 disposed in communication andsubstantial alignment with screw hole 26. Opening 48 is configured toguide a fastener into screw hole 26 relative to axis XB and insubstantial alignment with surgical pathway P. In some embodiments, thecross section configurations of screw holes 24, 26 may be, such as, forexample, oval, oblong, triangular, square, polygonal, irregular,uniform, non-uniform, offset, staggered, undulating, arcuate, variableand/or tapered. In some embodiments, surface 22 may have alternatesurface configurations to define cavities, similar to screw holes 24,26, for receiving fasteners, such as, for example, nails or pins.

Spinal implant system 10 includes one or more fasteners 42, as shown inFIG. 15, for attaching cage 12 with tissue, as described herein. In someembodiments, fasteners 42 may be engaged with tissue in variousorientations, such as, for example, series, parallel, offset, staggeredand/or alternate vertebral levels. In some embodiments, one or more offasteners 42 may comprise multi-axial screws, sagittal angulationscrews, pedicle screws, mono-axial screws, uni-planar screws, facetscrews, fixed screws, tissue penetrating screws, conventional screws,expanding screws, wedges, anchors, buttons, dips, snaps, frictionfittings, compressive fittings, expanding rivets, staples, nails,adhesives, posts, fixation plates and/or posts.

Each fastener 42 comprises a first portion, such as, for example, a headand a second portion, such as, for example, an elongated shaftconfigured for penetrating tissue. The head includes an engagementportion configured for engagement with a surgical instrument. The shafthas a cylindrical cross section configuration and includes an outersurface having an external thread form. In some embodiments, theexternal thread form may include a single thread turn or a plurality ofdiscrete threads. In some embodiments, other engaging structures may belocated on the shaft, such as, for example, nail configuration, barbs,expanding elements, raised elements and/or spikes to facilitateengagement of the shaft with tissue, such as, for example, vertebrae.

In some embodiments, all or only a portion of the shaft may havealternate cross section configurations, such as, for example, oval,oblong, triangular, square, polygonal, irregular, uniform, non-uniform,offset, staggered, undulating, arcuate, variable and/or tapered. In someembodiments, the outer surface of the shaft may include one or aplurality of openings. In some embodiments, all or only a portion of theouter surface of the shaft may have alternate surface configurations,such as, for example, smooth and/or surface configurations to enhancefixation with tissue, such as, for example, rough, arcuate, undulating,porous, semi-porous, dimpled, polished and/or textured. In someembodiments, all or only a portion of the shaft may be cannulated.

In assembly, operation and use, as shown in FIGS. 1-15, spinal implantsystem 10, similar to the systems described herein, is employed with asurgical procedure for treatment of a spinal disorder, such as thosedescribed herein, affecting a section of a spine of a patient. System 10may also be employed with other surgical procedures. To treat theaffected section of vertebrae V of a subject body B of a patient, body Bis disposed in a side orientation, as shown in FIGS. 1 and 2, relativeto a surgical fixed surface, such as, for example, surgical table Tconfigured for supporting body B. Body B is placed on a side, left sideup. In some embodiments, this results in the vena cava being oriented onthe right side of centerline. Body B is oriented such that the procedurecan be performed obliquely in front of the iliac crest to provide directaccess to L5-S1 intervertebral space along surgical pathway P, describedherein, while avoiding selected muscular and abdominal anatomicalstructures. In some embodiments, placement of body B on its sidefacilitates access to surgical pathway P that is disposed at obliqueangle α relative to axis XB.

A marking, as shown in FIG. 2, is drawn from the anterior of body B tothe posterior of body B to identify the slope and lordosis of the L5-S1intervertebral space and the line is continued along the same trajectoryas the slope onto the abdomen for accessing surgical pathway P. Theamount of slope visually indicates the most caudal, toward the coccyx,aspect of the incision to enter the lordosis of the L5-S1 intervertebralspace with respect to the cephalad, towards the head. A second line isdrawn from the center of the disc and projecting perpendicular to thefloor onto the abdomen. This line represents the actual level of thedisc in the abdomen. An incision I, as shown in FIGS. 2 and 3, is madewith a surgical instrument, such as, for example, a scalpel T2, forsubstantial alignment and communication to create surgical pathway Pfrom posterio-rostral to antero-caudal medial approximately 1-2 fingerbreaths from the ASIS and pelvis, between the two lines. In someembodiments, the incision can extend to higher levels of the spine anddistally to the symphisis pubis. In one embodiment, a separate L5-S1incision is utilized at a site lower and more anterior than the L4-L5.

In some embodiments, the external oblique muscle or the aponeurosis andfascia are encountered upon entry into incision I. In some embodiments,the retroperitoneal dissection and exposure is accomplished by utilizinga blunt finger so as to facilitate a wider exposure for the retractors.In some embodiments, the ureter is exposed and dissection of a widerostral to caudal development of the retroperitoneal plane is utilizedto protect the ureter, thereby maintaining its attachment to theposterior peritoneum while mobilizing anteriorly.

In some embodiments, surgical pathway P is created with the progressionof the two finger dissection down the pelvis and across the psoascontinues anteriorly from the pelvis to locate the iliac artery pulse.In some embodiments, the finger dissection is continued past thepulsating iliac artery medial to the artery on the sacral promontory andthe L5-S1 intervertebral space. In some embodiments, lighted retractorsare placed sequentially down onto the anterior spine and the adventitiallayers that are on the anterior disc and sacrum are encountered.

In some embodiments, the oblique approach creating surgical pathway Paccesses the L5-S1 intervertebral space below the bifurcation, as such,the iliolumbar vein is not ligated since posterior retraction of theleft common iliac vein and artery laterally does not cause stretch andpotential avulsion. In some embodiments, the L4/L5 is anteriorlyretracted and an implant can be inserted obliquely thereby avoidingmobilization of the vessels.

In some embodiments, as shown in FIG. 4, a surgical instrument, such as,for example, a retractor T3 is disposed with incision I and incommunication with surgical pathway P for spacing tissue. Retractorblades b1, b2, b3 are inserted sequentially around the L5-S1intervertebral space to protect vessels. A lateral or posterior blade b1is placed under the iliac vein to release the adventitial layer tosecure protection and lateralization of the left iliac vein and artery.Blade b1 may be provided with an elevation that permits directvisualization of a smooth pin (not shown) placement. In someembodiments, the pin is blunt nosed to push away vascular structures andthe threads are smooth to prevent wrapping up soft tissue. In someembodiments, a screw is malleted or screwed in and secures on one sideof blade b1. As shown generally in FIGS. 4A and 4B, blades b1, b2 and b3may be provided with channels 411, 412, 413 a, 413 b, through whichsecuring pins may be placed to secure the blades relative to the bonyanatomy of the surgical site.

An anterior blade b2 is disposed with incision I and about the L5-S1intervertebral space. In one embodiment, a final cephalad blade b3 isdisposed with the L5-S1 intervertebral space to protect the vascularbifurcation. In one embodiment, an additional blade may be placedcaudally to create a completely closed surgical pathway. In someembodiments, an annulotomy and/or discectomy is performed with asurgical instrument T4 with x-ray confirmation of the starting pointthat is central on the L5-S1 intervertebral space. In some embodiments,system 10 includes a semi-constrained retractor that facilitates minimaltissue pressures on surrounding abdominal structures and providesflexibility such that its blades rotate on a fixed pin allowing greaterdegrees of freedom of movement and working angles for a practitioner.

In some embodiments, as shown in FIGS. 4A and 4B, a semi-constrainedretractor system with separable blades may be used to sequentiallyinsert blades b1, b2, b3. Alternatively, the blades b1, b2, b3 may beremovably secured to a handheld retractor T3 via a system of pins 431,432, 433 on each blade that may be removably engaged with complementaryrecesses 421, 422, 432 defined in the proximal ends of blades b1, b2,b3. The blades b1, b2, b3 may also be fitted with attachment rods 401,402, 403 configured to be capable of securing to a frame, handle, orother attachment mechanism so as to be individually or simultaneouslymanipulated when either attached or not attached to the handheldretractor T3. The retractor T3 may be provided with three arms 441, 442,443 for manipulating the blades b1, b2, b3 when they are attachedthereto. Arms 441, 442 may be capable of spreading blades b1, b2 awayfrom one another along a generally anterior-posterior direction.Furthermore a third arm 443 may be capable of translating to move theblade b3 in the cephalad direction, see FIG. 12, for example, showing anexemplary position of blade b3. Arms 441, 442 may be engaged in aratcheting mechanism 446 such that handheld manipulation of theretractor T3 by a surgeon may hold the blades b1, b2 apart at a selecteddistance defined in part by the ratcheting mechanism 446. Arm 443 mayhave a separate ratcheting slide 445, allowing a surgeon toindependently manipulate and hold blade b3 at a selected distance in thefrom the blades b1, b2.

In one embodiment, a cephalad blade b3 is oriented toward thevasculature bifurcation near L5-S1 to secure protection of the vesselsat the bifurcations BA, BV (FIG. 12). Anterior blade b2 and posteriorblades b1 and b2 are oriented about the L5-S1 intervertebral space toprotect the remaining vessels caudal to the bifurcations BA, BV. Bladesb1, b2, b3 may define channels 411, 412, 413 a, 413 b, through whichsecuring pins may be placed to secure the blades relative to the bonyanatomy of the surgical site. Blade b3 may have an elevation and/ordistal curvature that permits direct visualization of a smooth pinplacement. In some embodiments, securing pin is blunt nosed to push awayvascular structures and the threads are smooth to prevent wrapping upsoft tissue. In some embodiments, a screw is malleted or screwed in andsecures on one side of blade b1, for example in channel 411. In someembodiments, blade b3 may be equipped with a curved distal end to sweepand/or elevate vascular structures, such as the bifurcations BA, BV,shown in FIG. 12, away from the surgical site. In one embodiment,anterior blade b3 may be provided with sensors S for detecting and/ormeasuring blood flow near the surgical site to ensure that the mostrelevant and sensitive vascular structures near the surgical site aresafely separated from the oblique-lateral and/or oblique spinal surgicalpathway. Sensors S may include, such as, for example, piezoelectricelements; ultrasound emitters and/or receivers, flowmeters; oximeters;pulse meters; and/or other available medical devices useful foridentifying and/or localizing blood vessels. In some embodiments,anterior blade b3 may be clear, translucent, or a substantially clearmaterial, such as, for example, a clear polymer, to allow a surgeon todirectly visualize structures on the anterior side of anterior blade b3during the surgical procedure.

In one embodiment, as shown in FIGS. 5 and 6, system 10, similar to thesystems and methods described herein, includes a flexible orsemi-constrained retractor, which is not attached to a rigid frame andfacilitates adjustment and allows for freedom of movement whenmanipulating implants, as described herein. A surgical instrument, suchas, for example, a retractor T5 is provided with downward oriented tips500 configured for engagement with corresponding pin holes 502 definedin individual retractor blades 504, 506, 508. As shown in FIG. 6, thepositioning of blades 504, 506, 508 may correspond to the relativepositioning of blades b1, b2, b3 shown generally in FIG. 12. RetractorT5 is configured to facilitate spacing of adjacent or opposing blades504, 506, 508. In one embodiment, pin holes 502 in retractor blades 504,506, 508 are configured to receive other surgical instruments, such as,for example, lighting tubes, pins for securing at least one of blades504, 506, 508 to a bony structure, the downward facing tips attached toa second retractor, or rubber bands.

In one embodiment, as shown in FIG. 6A, similar to the systems andmethods described herein with respect to FIGS. 4A and 4B, includes aflexible or semi-constrained retractor T16 having spacing for a threefinger manipulation. Retractor T16 includes a flexible arm attachment1612 for connection to a fixed point, such as a pin or frame rigidly oradjustable attached to an operating table. Retractor T16 includes tips1600 that are configured for engagement with central pivot holes 1602defined in individual retractor blades 1604 and 1608. Retractor T16includes a shoulder 1610 mounted with a retractor blade 1606. Shoulder1610 includes a ratchet 1614 for adjustment of blade 1606 position andone way locking. Shoulder 1610 includes a release 1616 that disengagesratchet 1614 to facilitate bi-directional movement of blade 1606.

In one embodiment, as shown in FIGS. 7 and 8, a surgical instrument,such as, for example, a specialized retractor blade T6 is shown thatfacilitates movement of vasculature with a securing pin 601, as shown inFIG. 8, or without a securing pin, as shown in FIG. 7. Retractor T6includes a blade 600 having a curved distal end 602 configured to safelymove or hold vasculature away from a surgical site while a surgeon isworking in the operative corridor. For example, the specialized blade T6may be used in lieu of or with the blades b1, b2, b3, for example, beingselectively attached to a handheld retractor T3 such as that describedherein with respect to FIGS. 4A and 4B. In one embodiment, as shown inFIG. 9, a surgical instrument is provided, such as, for example, aretractor T7 provided with two blades 702, 704 and a ratchet mechanism706 for incremental and controlled movement of blades 702, 704 at asurgical site. The retractor T7 may be a hand-held retractor formaintaining a surgical corridor by actuating a thumbwheel 705 thatactuates a mechanism for spreading the blades 702, 704 apart along asingle axis 701.

In one embodiment, as shown in FIGS. 10 and 11, system 10, similar tothe systems and methods described herein, includes a surgicalinstrument, such as, for example, a retractor T8, which includes blades802, 804, 806 that are configured to form a closed operative corridor.Blade 802 is disposed adjacent to the vessels, as described herein, andprotects the surrounding vessels. In one embodiment, blade 802 mayinclude a curved distal lip, similar to that shown as element 602 inFIG. 7, on a distal tip configured to protect vessels.

In one embodiment, as shown in FIGS. 12, 12A and 13, system 10, similarto the systems and methods described herein, includes a surgicalinstrument, such as, for example, a retractor T9, which comprises bladesB1, B2, B3 and can be manipulated and angled outside surgical pathway P.Blades B1, B2, B3 are disposed adjacent to the vessels, as describedherein, and protects the surrounding vessels. For example, the bladesB1, B2, B3 may be oriented and/or inserted independently or whileselectively attached to a handheld inserter, see, for example, retractorT3, shown in FIGS. 4A and 4B. In other embodiments, the blades B1, B2,B3 may comprise blades 504, 506, 508, as shown in FIG. 6, wherein eachblade is inserted separately, then manipulated into position relative tothe anatomy, as shown in FIG. 12. The blades 504, 506, 508 may then tospread and/or held open using a retractor, see, for example, retractorT5 described with regard to FIGS. 5 and 6, with downward facing tips 500that may be placed into holes 502. As shown in FIG. 12, in otherembodiments, the blades B1, B2, B3 may also be left unattached to aframe or retractor system such that they remain unconstrained where thesurgeon may manipulate each blade as necessary to maintain the operativecorridor along an oblique angle while still allowing sufficient mobilityof the blades to allow for instrument angulation to insert various trialinstruments, for example, as shown in FIGS. 17 and 18, cages 12, forexample, as shown in FIGS. 14-16 and 25-28, plates 132, for example, asshown in FIGS. 25-28), and fasteners 42, as shown, for example, in FIG.16.

As shown in FIGS. 12, 12A and 13, the blades B1, B2, B3 may bepositioned to maintain a safe surgical corridor near the aorticbifurcation BA and the inferior vena cava bifurcation BV. For example,blade B3 may be positioned to protect the bifurcations BA, BVthemselves, while blades B1, B2 may be positioned an configured withangled distal tips to sweep away and maintain spacing of the bifurcatedarterial and venous structures caudal to the bifurcations BA, BV.

In some embodiments, a discectomy is performed adjacent the L5-S1intervertebral space via surgical pathway P. In some embodiments,sequential trial implants are delivered along surgical pathway P andused to distract the L5-S1 intervertebral space and apply appropriatetension in the L5-S1 intervertebral space allowing for indirectdecompression. In some embodiments, the size of cage 12 is selectedafter trialing, cage 12 is visualized by fluoroscopy and oriented beforemalleting into the L5-S1 intervertebral space.

In some embodiments, trialing is utilized to establish a starting pointfor cage 12 insertion. In one embodiment, a trial instrument 1300, asshown in FIG. 17, includes a shaft 1308, a bubble level 1310 and asphere 1312 that is inserted into the L5-S1 intervertebral space. Anangle θ of trial instrument 1300 is adjusted via a handle 1314 until θequals angle α (wherein angle α denotes a desired oblique angle of thesurgical corridor as shown generally in FIGS. 14 and 15). Trialinstrument 1300 is visualized radiographically and/or visually in theanterior plane and the lateral plane to adjust sphere 1312 position to acenter of the disc space while maintaining angle θ. An intersection ofshaft 1308 and the vertebral body is marked by point 1350. Marked point1350 is a starting point for insertion of cage 12 at an angle θ. In someembodiments, marked point 1350 is aligned with a mark placed on thevertebral body, using a positioning trial instrument, such that thecombination of matching the angle of the inserter, via the bubble level,and matching the mark on the vertebral body to marked point 1350 placescage 12 in a selected position, for example, as determined by thepositioning trial instrument. In some embodiments, a practitionercenters cage 12 with the vertebral body, via, for example, radiographicmarkers, and aligns marked point 1350 with the mark on the vertebralbody, which may negate the need for a complementary bubble level orinclinometer on an inserter instrument T10, such as those describedherein with respect to FIGS. 19 and 20.

In one embodiment, as shown in FIGS. 18, 18A and 18B, a trial instrument1400, similar to trial instrument 1300 and methods of use describedherein, includes an offset shaft 1408 connected to an offset handle 1414and a cylinder 1412 that is inserted into the L5-S1 intervertebralspace. Offset handle 1414 provides indicia of the offset of cage 12insertion. Cylinder 1412 has a disc configuration and includes one ormore, for example, four orthogonal radio-opaque markers 1416 disposedcircumferentially about cylinder 1412. In some embodiments, fourorthogonal radio-opaque markers 1416 include an anterior marker, aposterior marker, and a marker on each lateral border of cylinder 1412.In some embodiments, markers 1416 align shaft 1408 at a selected angle,such as angle α, for example, such that the markers 1416 are in thecenter of the L5-S1 intervertebral space as viewed from an AP andlateral view of medical imaging, such as those described herein, andnear and far markers of cylinder 1412 are aligned and the position canbe marked on the vertebral body for implant insertion.

In some embodiments utilizing cage 12 secured with fasteners 42, pilotholes or the like are made in selected vertebra L5 and S1 of vertebrae Vadjacent the L5-S1 intervertebral space, via surgical pathway P, asshown for example, in FIG. 14, for receiving bone fasteners 42. InserterT1 is attached with cage 12 adjacent oblique surface 44. Inserter T1delivers cage 12 through incision I along surgical pathway P adjacent toa surgical site for implantation adjacent the L5-S1 intervertebralspace. Anterior surface 14 faces an anterior side of body B adjacentanterior portion A1 and posterior surface 16 faces a posterior side ofbody B, as described herein. Surface 18 engages endplate tissue ofendplate E1 and surface 20 engages endplate tissue of endplate E2.

Screw holes 24, 26 are oriented with the body of cage 12 in substantialalignment with surgical pathway P, as described herein. Screw hole 24 isoriented to receive a fastener 42 a via surgical pathway P and isdisposed at an angular orientation such that fastener 42 a is deliveredto the L5-S1 intervertebral space via surgical pathway P and oriented topenetrate endplate tissue of endplate E2, as shown in FIG. 15. Opening46 guides fastener 42 a into screw hole 24 relative to axis XB and insubstantial alignment with surgical pathway P. Screw hole 26 is orientedto receive a fastener 42 b via surgical pathway P and is disposed at anangular orientation such that fastener 42 b is delivered to the L5-S1intervertebral space via surgical pathway P and oriented to penetrateendplate tissue of endplate E1. Opening 48 guides fastener 42 b intoscrew hole 26 relative to axis XB and in substantial alignment withsurgical pathway P. A driver (not shown) is disposed adjacent the L5-S1intervertebral space and is manipulated to drive, torque, insert orotherwise connect bone fasteners 42 a, 42 b adjacent the L5-S1intervertebral space.

Upon completion of a procedure, as described herein, the surgicalinstruments, assemblies and non-implanted components of spinal implantsystem 10 are removed and the incision(s) are closed. One or more of thecomponents of spinal implant system 10 can be made of radiolucentmaterials such as polymers. Radiopaque markers may be included foridentification under x-ray, fluoroscopy, CT or other imaging techniques.In some embodiments, the use of surgical navigation, microsurgical andimage guided technologies may be employed to access, view and repairspinal deterioration or damage, with the aid of spinal implant system10. In some embodiments, spinal implant system 10 may include one or aplurality of plates, connectors and/or bone fasteners for use with asingle vertebral level or a plurality of vertebral levels.

In one embodiment, spinal implant system 10 includes an agent, which maybe disposed, packed, coated or layered within, on or about thecomponents and/or surfaces of spinal implant system 10. In someembodiments, the agent may include bone growth promoting material, suchas, for example, bone graft to enhance fixation of the components and/orsurfaces of spinal implant system 10 with vertebrae. In someembodiments, the agent may include one or a plurality of therapeuticagents and/or pharmacological agents for release, including sustainedrelease, to treat, for example, pain, inflammation and degeneration.

One embodiment, as shown in FIG. 16, comprises a spinal constructincluding cage 12, described above, and a complementary plate 132delivered through incision I along surgical pathway P adjacent to asurgical site for implantation adjacent the L5-S1 intervertebral space(FIG. 18). Plate 132 has a portion 138 configured to engage a vertebra,such as, for example, the L5 vertebra and a portion 140 configured toengage a vertebra, such as, for example, the S1 vertebra. In oneembodiment, plate 132 may be attached with implant 12 prior toimplantation or in situ. Plate 132 includes an inner surface 134 thatdefines openings 136 configured to receive fasteners 42, describedherein. Fasteners 42 a are configured for fixation with the S1 vertebraand fasteners 42 b are configured for fixation with the L5 vertebra. Inone embodiment, plate 132 is secured with implant 12 via a fastener. Insome embodiments, plate 132 includes a back out prevention element 133.

In one embodiment, as shown in FIGS. 19-28, system 10, similar to thesystems and methods described herein, comprises a spinal constructincluding cage 12 and plate 132, described above. Plate 132 includes acollet opening 160, as shown, for example, in FIGS. 25-28, configuredfor engagement with a surgical instrument, such as, for example, aninserter T10. Inserter T10 includes a body attachable to the spinalconstruct and a shaft connected with the body for manipulating thespinal construct.

Inserter T10 attaches to plate 132 at opening 160 via the componentsand/or mating parts of inserter T10 and the spinal construct to deliverplate 132 and/or cage 12 through incision I along surgical pathway Padjacent to a surgical site for implantation adjacent the L5-S1intervertebral space.

In one embodiment, as shown in FIGS. 19 and 20, inserter T10 includesimage guidance and/or surgical navigation to monitor, maintain, adjustand/or confirm disposal, delivery and/or alignment of the components ofsystem 10 along surgical pathway P and/or adjacent to a surgical site.For example, the surgical navigation components of system 10 facilitateplacement of cage 12 with the L5-S1 intervertebral space. The surgicalnavigation components of system 10 include an emitter 1510 configured togenerate a signal representative of a position of inserter T10 and/orcage 12 connected therewith, for example, along surgical pathway Pand/or adjacent to a surgical site such as the L5-S1 intervertebralspace. In some embodiments, emitter 1510 may include one or a pluralityof emitters. In one embodiment, emitter 1510 is shaped substantiallylike the Greek letter pi and comprises four spaced apart emitters 1511,for generating a signal representing the trajectory of inserter T10and/or cage 12 relative to a portion of a patient's anatomy and thedepth of inserter T10 and/or cage 12 along surgical pathway P and/oradjacent to a surgical site. In one embodiment, emitter 1510 includes atleast one light emitting diode. In some embodiments, emitter 1510 mayinclude other tracking devices capable of being tracked by acorresponding sensor array, such as, for example, a tracking device thatactively generates acoustic signals, magnetic signals, electromagneticsignals, radiologic signals. In some embodiments, emitter 1510 may beremovably attached to inserter T10. In some embodiments, emitter 1510may be integrally formed with inserter T10 such that inserter T10 is amonolithic, unitary body.

In some embodiments, system 10 includes a tracking device (not shown)having an emitter array including one or a plurality of emitters thatgenerate signals representing the position of various body referencepoints of the patient's anatomy. A sensor (not shown) receives signalsfrom emitter 1510 and the array. The sensor communicates with aprocessor (not shown), such as, for example, a digitizer control unit,which processes the signals from emitter 1510 and the array to provideinformation regarding the trajectory of inserter T10 and/or cage 12relative to a portion of the patient's anatomy and the depth of inserterT10 and/or cage 12 along surgical pathway P and/or adjacent to asurgical site. The processor sends this information to a monitor, whichprovides a visual representation of the position of inserter T10 and/orcage 12 along surgical pathway P and/or adjacent to a surgical site toallow the medical practitioner to guide inserter T10 and/or cage 12 to adesired location within the patient's anatomy.

The monitor is configured to generate an image from a data set stored ina controller, such as, for example, a computer. In some embodiments, thedata set may be generated preoperatively using scanning techniques, suchas, for example, a CAT scanner or MRI scanner. The image data setincludes reference points for at least one body part, such as, forexample, the spine of a patient, which has a fixed spatial relation tothe body part. The processor is connected to the monitor, under controlof the computer, and to inserter T10 and/or cage 12.

The sensor receives and triangulates signals generated by emitter 1510and the array to identify the relative position of each of the referencepoints and inserter T10 and/or cage 12. The processor and the computermodify the image data set according to the identified relative positionof each of the reference points during the procedure. The position andtrajectory of inserter T10 and/or cage 12 provided by emitter 1510 andthe array is processed by the processor and the computer and is visuallydisplayed against the preoperative image data set stored in the computerto provide the medical practitioner with a visual representation of thetrajectory of inserter T10 and/or cage 12 relative to a portion of thepatient's anatomy and the depth of inserter T10 within the patient'sanatomy. See, for example, similar surgical navigation components andtheir use as described in U.S. Pat. Nos. 6,021,343, 6,725,080,6,796,988, the entire contents of each of these references beingincorporated by reference herein.

In use, as shown in FIGS. 21-28, a modular drill, tap, and screw (DTS)guide 1520 mates with a shaft 1522 of inserter T10. Inserter T10 has amale protrusion that is aligned into a female connection on shaft 1522.A thread cap 1524 is manipulated to create a secure connection betweenshaft 1522 and DTS guide 1520. DTS guide 1520 is mated with cage 12 andplate 132, as shown in FIG. 22. The DTS guide 1520 may be provided infour-hole embodiments (see FIGS. 19-20, for example) for guiding drills,taps and screws for implanting a plate 132 and cage 12 embodiment. Insuch embodiments, the DTS guide may define holes or channels suitablefor guiding fasteners 43 a-43 d (see FIG. 25) into the correspondingholes defined in the plate 132. In other embodiments, the DTS guide 1520may comprise a two-hole embodiment (see FIG. 14, for example) suitablefor guiding drills, taps and screws for implanting a cage-onlyembodiment. In such examples, as shown generally in FIG. 15, thefasteners 42 a, 42 b may comprise bone screws angled so as to enter theendplate E1 of either the sacrum S1 or the vertebral body V1.

In some embodiments, a specific size cage 12 and plate 132 are loadedinto a loading block of system 10. Inserter T10 is placed onto plate 132and into a side shelf on plate 132. An actuator 1526 of a handle 1528 isrotated clockwise to rigidly affix inserter T10, cage 12 and plate 132together. Cage 12 and plate 132 can be delivered and implanted with theL5-S1 intervertebral space via inserter T10, as described above withregard to FIGS. 1-16.

In some embodiments, after implantation of cage 12 and plate 132, apractitioner can manipulate actuator 1526 counter clockwise to loosenthe connection of T10, cage 12 and plate 132. This configuration allowsplate 132 to toggle relative to cage 12, which provides cage 12 andplate 132 relative freedom of movement such that the practitioner canmaneuver the spinal construct for final placement of cage 12 and/orplate 132. In some embodiments, plate 132 can rotate relative to cage 12about an anterior face of cage 12 in a range of approximately 20degrees, as shown in FIGS. 27 and 27A.

Inserter T10 is an adaptable instrument configured to perform multipleapplications during a surgical procedure. In some embodiments, inserterT10 can prepare and/or create a cavity in tissue, such as, for example,bone. Inserter T10 guides a surgical instrument, such as, for example, adrill, tap and/or an awl, as well as guiding fasteners to penetratetissue. In some embodiments, inserter T10 implants fasteners at anoblique angle with final placement centered on a midline of a sagittalplane. In some embodiments, inserter T10 is a guide that holds plate 132and cage 12 together. Surgical instruments including an awl, a tap andscrews are passed through inserter T10.

FIGS. 29A-31B show an alternative embodiment of the inserter T1 and cage12 shown generally in FIGS. 14 and 15 in preparation for implantation inthe intervertebral space between the sacrum S1 and the L5 vertebral bodyV1. In such embodiments, the inserter T1 may be modified from theembodiment shown in FIGS. 14 and 15 to include a stop element 3001. Thestop element 3001 may comprise an extension from the inserter T1,providing a physical stop to prevent the inserter T1 from beingover-inserted into the intervertebral space. As shown in FIG. 30A, thestop element 3001 may comprise a planar lateral surface 3002 placed sothat the lateral surface 3002 may be used as a guide for propertlyaligning the implant for insertion along the oblique angle α (see FIGS.14 and 15, for example and the description herein relative to FIGS. 30Aand 30B). Furthermore, the cage 12 may be provided with an obliquemarking 3003 on a contralateral side opposing the oblique insertionsurface of the cage 12 that also serves as a visual guide to the surgeonfor establishing and maintaining the oblique insertion pathway.

In such embodiments, a surgeon may make a midline mark M1, using acauterizing or electrosurgical instrument (or other marking device) onthe vertebral body V1 to mark the true midline of the vertebral body V1.Then, as shown generally in FIGS. 30A and 308, the surgeon may line upthe oblique marking 3003 of the cage 12 with the midline mark M1 on thevertebral body V1. A proper oblique insertion pathway (see angle α shownin FIG. 14, for example) may then be established by visualizing animaginary line from the oblique marking 3003 to the lateral surface 3002of the stop element 3001. In some embodiments, a proximal (handle) endof the inserter T1 may also be fitted with an inclinometer or bubblelevel corresponding to a similar instrument (see element 1310 in FIG.17) such that the oblique insertion pathway a may be established and/orverified by comparison to the angle α established using a trial 1300,1400 (see FIGS. 17 and 18).

FIGS. 31A and 31B show the cage 12 fully seated in the intervertebralspace between the sacrum S1 and the L5 vertebral body V1. When the cage12 is fully seated in these embodiments, the midline mark M1 on thevertebral body V1 should line up with the lateral surface 3002 of thestop element 3001. Once the angle and orientation of the cage 12 isverified in this way, the inserter T1 may be disengaged (viadisengagement of a threaded inserter rod as described further herein)from the cage 12 and retracted along the insertion pathway α. It shouldbe understood that the various cage 12, inserter T1 and marking method(see M1) modifications described herein relative to FIGS. 29A-31B mayalso be applied to other cage and inserter embodiments described herein,including but not limited to the cage 12 and plate 132 embodiments ofFIGS. 19-28.

It will be understood that various modifications may be made to theembodiments disclosed herein. Therefore, the above description shouldnot be construed as limiting, but merely as exemplification of thevarious embodiments. Those skilled in the art will envision othermodifications within the scope and spirit of the claims appended hereto.

1-20. (canceled)
 21. A surgical instrument comprising: a handle; a firstmember extending along a first longitudinal axis, the first member beingconnected to the handle by a pin that extends parallel to the firstlongitudinal axis, the pin being received in a recess of the firstmember, the first member being engageable with tissue of a substantiallyposterior portion of an incision relative to a body, the first memberbeing rotatable relative to the handle about the first longitudinalaxis; a second member connected with the handle and extending along asecond longitudinal axis that extends parallel to the first longitudinalaxis, the second member being engageable with tissue of a substantiallyanterior portion of the incision relative to the body, the second memberbeing rotatable relative to the handle about the second longitudinalaxis, the first and second members being rotatable relative to oneanother about a pivot axis that extends parallel to the first and secondlongitudinal axes; and a third member connected with the handle andengageable with tissue of a substantially cephalad portion of theincision relative to the body, the members being disposable in aconfiguration to space the tissue to define an oblique surgical pathwayrelative to a bilateral axis of the body.
 22. A surgical instrument asrecited in claim 21, wherein each of the members includes an axialcavity configured for disposal of a pin engageable with bone adjacentthe pathway to fix the members relative to the bone.
 23. A surgicalinstrument as recited in claim 21, wherein at least one of the membersincludes spaced axial cavities.
 24. A surgical instrument as recited inclaim 21, wherein the handle includes arms that are independentlyconnected with the first and second members to rotate the first andsecond members about the pivot axis.
 25. A surgical instrument asrecited in claim 24, wherein the pin is fixed relative to one of thearms.
 26. A surgical instrument as recited in claim 24, wherein each ofthe arms is independently movable such that the members can beindependently and selectively movable relative to the other members. 27.A surgical instrument as recited in claim 24, wherein the first andsecond members are relatively and selectively movable in a substantiallyanterior-posterior direction.
 28. A surgical instrument as recited inclaim 24, wherein the third member is selectively movable in asubstantially cephalad direction relative to the first and secondmembers.
 29. A surgical instrument as recited in claim 21, wherein thehandle includes a ratchet.
 30. A surgical instrument as recited in claim21, wherein at least one of the members includes a distal curvature. 31.A surgical instrument as recited in claim 21, wherein at least one ofthe members includes a sensor for detecting and/or measuring vasculardata.
 32. A surgical instrument as recited in claim 21, wherein at leasta portion of at least one of the members is translucent.
 33. A surgicalinstrument as recited in claim 21, wherein the handle comprises firstand second arms that are connected to the first and second members and athird arm that is connected to the third member, the third arm extendingthrough the pivot axis.
 34. A surgical instrument as recited in claim33, wherein the third arm defines a slide axis that extendsperpendicular to the pivot axis, the third arm being configured to movein opposite directions along the slide axis to move the third memberrelative to the first and second members.
 35. A surgical instrument asrecited in claim 34, wherein the third arm extends through a ratchetingslide of the handle that is configured to prevent movement of the thirdarm along the slide axis.
 36. A surgical instrument as recited in claim33, wherein the handle includes a ratcheting mechanism that is fixed tothe first arm and extends through the second arm, the ratchetingmechanism being configured to prevent rotation of the first memberrelative to the second member.
 37. A surgical instrument as recited inclaim 21, wherein the members each include a channel that extendsparallel to the axes through opposite top and bottom surfaces of themembers.
 38. A method for treating a spine, the method comprising thesteps of: providing the surgical instrument recited in claim 21;sequentially disposing the members such that the first member engagestissue of the substantially posterior portion of the incision relativeto the body, the second member engages tissue of the substantiallyanterior portion of the incision relative to the body and the thirdmember engages tissue of the substantially cephalad portion of theincision relative to the body; and selectively orienting the members ina configuration to space the tissue to define an oblique surgicalpathway relative to a bilateral axis of the body.
 39. A surgicalinstrument comprising: a handle; a posterior blade connected with thehandle and extending along a first longitudinal axis, the posteriorblade being connected to the handle by a first pin that extends parallelto the first longitudinal axis, the first pin being received in a recessof the posterior blade, the posterior blade being rotatable relative tothe handle about the first longitudinal axis; an anterior bladeconnected with the handle and extending along a second longitudinal axisthat extends parallel to the first longitudinal axis, the anterior bladebeing connected to the handle by a second pin that extends parallel tothe second longitudinal axis, the second pin being received in a recessof the anterior blade, the anterior blade being rotatable relative tothe handle about the second longitudinal axis, the blades beingrotatable relative to one another about a pivot axis that extendsparallel to the first and second longitudinal axes; and a cephalad bladeconnected with the handle, wherein the blades are disposable in aconfiguration to space tissue of an incision to define an obliquesurgical pathway relative to a bilateral axis of a body.
 40. A surgicalinstrument as recited in claim 39, wherein the handle is independentlyconnected with the blades such that each of the blades can beindependently and selectively movable relative to the other blades.